Macular Degeneration (cont.)

Andrew A. Dahl, MD, FACS

Andrew A. Dahl, MD, is a board-certified ophthalmologist. Dr. Dahl's educational background includes a BA with Honors and Distinction from Wesleyan University, Middletown, CT, and an MD from Cornell University, where he was selected for Alpha Omega Alpha, the national medical honor society. He had an internal medical internship at the New York Hospital/Cornell Medical Center.

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

What is wet age-related macular degeneration?

Wet AMD occurs when abnormal blood vessels grow from the choroid (the layer of blood vessels between the retina and the outer firm coat of the eye called the sclera) under and into the macular portion of the retina. These new blood vessels (known as choroidal neovascularization or CNV) tend to be very fragile and often leak blood and fluid. The blood and fluid raise the macula from its normal place at the back of the eye and interfere with the retina's function and causes the central vision to blur. Under these circumstances, vision loss may be rapid and severe. Some patients, however, do not notice visual changes despite the onset of CNV. Therefore, periodic eye examinations are very important for patients at risk for CNV.

Once CNV has developed in one eye, whether there is a visual loss or not, the other eye is at relatively high risk for the same change.

All wet AMD is described as advanced AMD, whether or not there is serious visual loss. Wet AMD does not have not have stages like dry AMD. The wet form generally leads to significantly more vision loss than the dry form.

All people who have the dry form of AMD are at risk for development of the wet form. All people who have the wet form had the dry form first. The dry form can advance and cause vision loss without turning into the wet form. The dry form also suddenly can turn into the wet form. Currently, there is no certain way to predict if or when the dry form will turn into the wet form.

What are retinal drusen?

Retinal drusen are yellow deposits under the retina. They often are found in people over 60 years of age. Your eye-care professional can detect drusen during a comprehensive dilated eye exam.

Drusen alone do not usually cause vision loss. In fact, scientists are unclear about the connection between drusen and AMD. It is not clear if an increase in the size or number of drusen raises a person's risk of developing either advanced dry AMD or wet AMD.